Use autoconf for _Py_STACK_GROWS_DOWN

Author: encukou

Include/internal/pycore_ceval.h

@@ -16,12 +16,6 @@ extern "C" {
 #include "pycore_stats.h"         // EVAL_CALL_STAT_INC()
 #include "pycore_typedefs.h"      // _PyInterpreterFrame
 
-/* HP PA-RISC has a stack that goes up */
-#ifdef __hppa__
-#  define _Py_STACK_GROWS_DOWN 0
-#else
-#  define _Py_STACK_GROWS_DOWN 1
-#endif
 
 /* Forward declarations */
 struct _ceval_runtime_state;

Include/pyport.h

@@ -682,4 +682,10 @@ extern "C" {
 #endif
 
 
+// Assume the stack grows down unless specified otherwise
+#ifndef _Py_STACK_GROWS_DOWN
+#  define _Py_STACK_GROWS_DOWN 1
+#endif
+
+
 #endif /* Py_PYPORT_H */

configure

@@ -1202,6 +1202,14 @@ if test x$MULTIARCH != x; then
 fi
 AC_SUBST([MULTIARCH_CPPFLAGS])
 
+# Guess C stack direction
+AS_CASE([$host],
+  [hppa-*], [_Py_STACK_GROWS_DOWN=0],
+  [_Py_STACK_GROWS_DOWN=1])
+AC_DEFINE_UNQUOTED([_Py_STACK_GROWS_DOWN], [$_Py_STACK_GROWS_DOWN],
+  [Define to 1 if the machine stack grows down (default); 0 if it grows up.])
+AC_SUBST([_Py_STACK_GROWS_DOWN])
+
 dnl Support tiers according to https://peps.python.org/pep-0011/
 dnl
 dnl NOTE: Windows support tiers are defined in PC/pyconfig.h.

configure.ac

@@ -2026,6 +2026,9 @@
 /* HACL* library can compile SIMD256 implementations */
 #undef _Py_HACL_CAN_COMPILE_VEC256
 
+/* Define to 1 if the machine stack grows down (default); 0 if it grows up. */
+#undef _Py_STACK_GROWS_DOWN
+
 /* Define if you want to use tail-calling interpreters in CPython. */
 #undef _Py_TAIL_CALL_INTERP